The Best Monster Cookie Bars

These delicious Monster Cookie Bars are one of my favorite treats. They are fully loaded with peanut butter, chocolate chips, and M&Ms, and come out perfectly thick and chewy every time. They are always a huge hit and never last long when I make them!

Course Dessert, Snack

Cuisine American

Prep Time 10

Cook Time 35

Total Time 45

Servings

Calories 348

Author Ashlyn Edwards | Belle of the Kitchen

Ingredients

1 cup unsalted butter 2 sticks
1 cup peanut butter or nut butter alternative, *see notes
1 cup packed brown sugar
3/4 cup granulated white sugar
2 eggs
2 teaspoons vanilla extract
2 cups all purpose flour
2 cups old fashioned oats
1 teaspoon baking soda
1/2 teaspoon salt
1 cup semi-sweet chocolate chips
1 cup M&M candies

Instructions

Preheat the oven to 350 degrees Fahrenheit. Spray a 9x13 inch baking dish with cooking spray and set aside.
In a large bowl, cream together the softened butter, peanut butter, and sugars with an electric mixer until smooth and creamy, about two minutes. Scrape down the sides of the bowl as needed. Add in the eggs and vanilla and mix until blended.
Add the flour, oats, baking soda, and salt and mix on low speed until just combined.
Fold in the chocolate chips and M&Ms. Press the dough into the prepared baking pan using a spatula to smooth out the top.
Bake in the preheated oven for about 30-35 minutes until bars are golden brown and set. Don't overbake. Allow to cool slightly before cutting and enjoying!

Notes

Switch up the fillings. You can replace the chocolate chips with peanut butter chips, butterscotch chips, dark chocolate chips, or even nuts like walnuts or chopped pecans. You can also replace the M&M candies with another type of candy or use mini M&Ms.

Peanut butter alternatives: If you're looking for a peanut free version of monster cookie bars, consider making these with your favorite nut butter alternative like almond butter, cashew butter, etc. Just make sure whatever you choose is creamy, not crunchy. My favorite is Wow Butter; it's made from soy, is peanut and tree nut free, and tastes GOOD! It has a similar peanut butter flavor, and bakes perfectly in the bars. You could also use sunflower seed butter, but the flavor profile will be very different.

Make Monster Cookies instead! This dough can also be used for making cookies instead of bars. Simply line a sheet pan with parchment paper and use a cookie scoop to form the dough into balls. Bake the cookies for 10-12 minutes in a 350 degree oven until just set.

Store fully baked and cooled cookies in an airtight container on the counter for up to four days.

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